1. Field of the Invention
The present invention relates to a display device and a display device manufacturing method as well as a method of manufacturing the components of the display device. More particularly, the present invention is concerned with a display device including an electro-optic converting member, which can control an amount of transmitted light by utilizing an electric action, such as a liquid crystal cell, and also including a light control member for controlling refraction of light, a method of manufacturing the display device, and a method of manufacturing the components of the display device.
2. Description of the Related Art
To date, liquid crystal display devices have rapidly been evolved as one form of display device in various fields owing to the features of lower power consumption, thin design, low weight, and others. In particular, the liquid crystal display device is adopted for the majority of personal digital assistant equipment, including portable cellular phones, whose prevalence has grown in recent years.
Moreover, the liquid crystal display device adopted for the personal digital assistant equipment is designed with an emphasis on low power consumption for a longer service life of a battery. However, as the liquid crystal display device is not a type of display device that glows itself, it is hard to discern the display in an environment in which sufficient extraneous light is not available. Therefore, the personal digital assistant equipment has a backlight disposed as an auxiliary light source on one side of a liquid crystal cell opposite to the side at which a viewer exists. The liquid crystal display device having the backlight falls into a transmissive type and a transflective type. However, these types of liquid crystal display devices are very poor at efficient use of light.
A proposal has been made for a reflective liquid crystal display device including one polarizer and adopting a front light, which is disposed on the side of a liquid crystal cell on which a viewer exists, as an auxiliary light source. However, as a light guide plate for introducing light emitted from the front light is disposed on the side on which a viewer of the liquid crystal panel or cell lies, the liquid crystal display device is made thicker by the thickness of the light guide plate. Normally, as the light guide plate has a thickness of about 1 mm, the liquid crystal display device becomes thicker by 1 mm at a minimum. Moreover, when the front light is adopted, a light guide plate having unevenness is employed. Therefore, a protective plate called windshield must be placed on the external side of the light guide plate in order to protect the light guide plate from damage. This increases the thickness of the liquid crystal display device. In reality, when consideration is taken into the thickness of the windshield, an extra thickness of 3 mm is added to the thickness of the liquid crystal panel.
Japanese Unexamined Patent Application Publication No. 2001-33766 has proposed a liquid crystal display device having an auxiliary light source mounted on a lateral side thereof. The liquid crystal display device is of a reflective type having a reflecting layer formed on an outermost layer thereof. The reflective liquid crystal display device has a liquid crystal layer sealed with a sealing member between two transparent substrates. A first polarizing member supported using a double-faced adhesive is placed on the external side of one of the transparent substrates, and a light control member is disposed in a space between the first polarizing member and the first transparent substrate. A second polarizing member is layered on the external side of the other transparent substrate, and a reflective layer is formed on the external side of the second polarizing member.
When incident light approximates a line perpendicular to the surface of the light control member, the light control member transmits the light. When the incident light approximates a line horizontal to the surface thereof, the light control member reflects the light. The light control member is intended to increase an amount of light transmitted by the liquid crystal layer. A light source is in close contact with the lateral sides of the layered transparent substrates. The light control member reflects light, which emanates from the light source, in the direction in which liquid crystalline molecules are aligned.